Quantity indicator for liquids



2 Sheetsj-Sheet l July l, 1941. J. MAccALLuM, JR

QUANTITY INDICATOR FOR LIQUIDS Filed May 27, 1920 July 1, 1941. J. MACCALLUM, JR

QUANTITY INDICATOR FOR LIQUIDS 2 Sheets-Sheet 2 Filed May 27, 192g www,

Patented `Iuly 1, 1941 UNITED STATES PATENT FFICE 2,248,006 i p QUANTITY rulnmrroitFoa LrQUiDs James Maccallum, Jr.,v Louis, Mo. Applications/ray 27, 192e, serial No. 384,632

(ci. 'r3-303i 6 Claims.

This invention relates to improvement in quantity indicators for liquids, and has for its primary object an indicator so constructed and operated that the quantity of liquid in the container can be seen at a glance without the necesa sity of introducing a measuring stick into the container. i v

A further object is to construct a quantity indicator for liquids which has a submergedv compression chamber in such a manner that the volume of air in the compression chamber, which is absorbed by the liquid or varied by any other cause, may be maintained andv thus cause-the indicator to work and register properly by maintaining a constant working head at al1 times. Astill further object is to construct a quantity indicator for liquids in such a manner that air absorbed from the air pressure chamber is replaced by delivering additional air to the pressure chamber without draining the entire liquid container. l

. In the drawings:

Fig. 1 is a vertical sectionalview of a liquid container with my device in position, and showing a portion thereof in section.

Fig. 2 is an enlarged vertical sectional view of the air or compression chamber with parts broken away.

Fig. 3 is a top plan View of theair compression chamber.

Fig. 4 is a similar View with the housing ,or 'wp of the chamber removed. l

Fig. 5 is a fragmental section of a portion of the container, showing a modified form of construction.

Fig. 6 is a view partly in section and parts broken away showing one form of suction device.

In the construction of my device 5 represents a liquid container. This may be of any desired shape or construction, and is provided with a screw threaded neck 6, and a closing cap 1. This cap is provided with the vent 8 so as to admit air to the container so that liquid can be withdrawn.

In the bottom 9 of the container, I form an opening I through which is inserted a portion of the ring II, the portion I2 of the ring extending into the tank and forming a sediment trap. Extending from the portion I2 of the ring is a right angular projection I3, which is screw threaded as at I4. The portion I of the right angular projection is turned inward and is adapted to act as a bearing surface for the flange or edge I6. Formed integral with this flange I3 is a cup shaped member I1, which extends upwardly and into the container. This cup I1 is provided on its sides with a plurality of flutes or outwardly pressed portions I8. These portions are spaced apart as shown in Figs. 3 and 4 and leave the remaining edge I9 of the cup of the samediameter as the top of the casing 20 of theair pressure chamber 2|. This air pressure chamber is provided with a concave or. dishshaped bottom 22, which has a central depression 23. VVThis .depressionis provided with openings 24 through which air and liquid may enter the .air pressure chamber. The bottom is also provided with a central opening 25 through which the end 26 ofthe pipe ttng 21 projects. This iitting may be used for withdrawing the liquid from the container by gravity, or it may be used as a tting to which may be attached various kinds of pumps Iand suction devices for withdrawing the liquid. Formed integral with the flange I6 is a flanged projection 28, the ange of which is screw threaded as at 29. to receive the fitting 21. Secured between the cup I1. and the flange member 23 is a convex shield or baffle 33, the purpose of which is to deflect air bubbles toward the center and toward the projection 25 formed on the fitting 21. The cupy shaped member I1 and the shieldor baffle 30 are provided with openings 3I, which register with each other and communicate directly with the interior of the container.

Passing through one of the openings is a tube 324 which extends to a point near the top of the tank, and is for the purpose of introducing air beneath the baffle 3B. Secured within the top-of the housing 20 is a pipe 32a, which pipe extends upwardly and is secured in a fitting 33, which in turn extends through the wall of the tank'or container 5, and is held in vposition by means of a lock nut 34. To this tting is secured a pipe 35, which has a gauge or indicator 36 secured to itsopposite end. This gauge is adapted to indicate the amount of pressure conv tained in the chamber 2I and thus designate the amount of liquid in the container.

It is to be understood that the gauge 36 may be placed at any convenient place,` or at any desired distance from the tank.

'I'he fitting 21 is provided with a passageway 31, which communicates with the tank at a point located beneath thebalile 3D by means of a port 38, and the outer end 39 of the tting is so arranged as to enable a suction line 5I to be connected thereto which line is in turn 'Ihese screw threads are adapted connected to a conventional vacuum tank or other intermittent suction device 52.

, It will be seen by reference to Figs. 1 and 2 that the opening 38 through which the liquid within the container is withdrawn is in such proximity to the end of the tube 32, that supplies the air employed to replenish the pressure chamber 2| therewith, that there is a commingling of such delivered air with the liquid drawn through the opening 38 and the conduit 31, upon the periodic withdrawal of liquid incident tothe working of the apparatus. The result is, as is demonstrated in the practice of this invention, that upon a cessation of such liquid withdrawal the air that is commingled-With the liquid withdrawn and which is in the tting-21 and the conduit 31 passes back throughthe opening 38,7whence it is directed so asto be avail;- able for and utilized in maintaining the desired volume of air Within the chamber 2 I. .,Tlgleoperationl of my device is, as follows:

/ 'Aiterall o'f'fthefconnections have' been made andptightened the liquid is introduced into the container. VThis-,will gradually rise in the tank and also: flow .through the openings 3|', 40 andf 24p als well as through the flutes formed in the cup'Y |17. This. will commence` to compress the air irrthe chamber, 2| abovethe liquid, and; in turn; this pressure of air will be transferred to thetgauge". Ordinarily the liquid poured into the containerrises toany level A Fig. .1'. A portion ofetlfiellliquid will enter the pressure chamber 2l' ars-,stated aboveand rise to a level'B, suchv that the: air pressure in. the chamber Vjust balances thef'hydro'static' hea-d of the liquid in the tank;

When the liquid is withdrawnthr'ough thejfitting 21 thenthe space beneath the bale 30; of theair'; pressure chamber empties asrdoes the pipe-32. 'I'he openings 3| are so graduated in proportion to 'they inside diameter `of thepipe 32,

'l' `j that airtwill ow through the pipe faster than the: liquid iiows Ythrough the openings 3 |V and the opening llto take* place of the'liquidwithdrawn. Thisl air rises upwardand into thel pressure chamber, and .in event that the Volume of airy inV the' chamber has beenV reduced by any'l cause whatever; it i'sreplaced, and the balance of the air escapes from the. underside of the air pressure chamberr` .through the utes |8 and through the liquid-to the top of ,the container,.thus maintaining a-y 'constant workingv hea'd.`

`If, the liquid is withdrawn through thetting 2-1 faster .than it caribe replaced by flow through thefoplenihgs' 3| and 40a temporary partial vacuuni is' s'et. up `beneath fthe shield 3).

been: withdrawn; is replaced from' theV tankY and'` corne'inpontactfwith the under surface of the This will Vcanseffair to, be drawn through the pipe 32 and` This air'will` up with gasoline and the device rendered useless, and this would necessitate the removal of the iitting 21, and the complete draining of the tank or the container 5 in order to re-establish the balance of pressure required.

The cup |1 is made small enough so that by theremoval of the securing ring El the pressure chamber and its component parts can be removed from the container, it being necessary however iirst-toI remove the pipe and the lock nut 34.

I may, if desired, extend the pipe 32 up through the top of the tank; It is necessary that a constant volume of air be maintained in the pressurechamber' so that the working head or liquid level within the chamber can be maintained to exert pressure against this Volume of air. If the volume: of; air is varied, that is reduced, the liquid will rise in the air pressure 'chamber and the' weight of this additional liquid will act against. the working head of the liquid in the tank and causean error in the indication of the gauge.- the' volume of air in the pressure chamber is notfmaintained; constant by air replacement,. the? Working'headwill vary and the gangewilr not register accurately as pointed out above.

By-theuse oimy device, this working level or head1 andthe air vol-urne in the pressure chamber is, alwaysfmaintained constant by the automatic; suppiy oiA additiona'lair beneath the chamber,.;and. whenqthe volume of air therein increases, `as isy theY case' when the air expands due toa: rise in. t,ern-peratureorany` other cause', rthe air can passA out? through the openings 23- and 24 intherconcavebottom' ofv they Vpressure chamber and-into the? liquid container thus restoring the; working head. of the liquid against'the air inthe-pressure chamber..v During the withdrawal ofthe' liquid the air'in the pipe connection between the tank and the suction device or pump obviously becomes mixedY with the liquid while itpa'sses therethrough and'whenV the vacuum or suction?l ceasesfto, operate the miXed air and liquid in this connection returns by gravity to the liquid container throughV the passages 31 and 38 the fitting- 21'. and the entrapped air then Vrises upward through the liquid and passes through thepassageways 40; A certain amount shield, whichA will direct it toward the portion A 25 r`oifthe tt'ingf`, 2'1, the shieldl 3U being provided, with thel opening 4U, which is slightly larger ,than-the portion 26, will allow the" air wtol pass upwardY and lodge againstY the bottom 22 lofthe chanber 2|.. This bottoni beingf coric'aved will'r actas' an air trap, and when' suf- Q'erent airhas" lodged' against the bott-oma: tov displace enough liquid tir uncover" the Openings 24",; theair willi passfupw'ard-'and into the chamber'il;

' ]Z-"l'iavew f 'ourd'irom experience lthat liquids, especially gasoline; willi absorb airY arid-- inapressurechamber of myco'nstrucnori, were thisv arr;

not replaced, the'cliambje'r' would. Vgraduallynil 75 of this air also enters the pressure chamber Y through th'e'passag'eways 23y an'd'24, thus maintaining the volume of airini'thev chamber con- Y claim is:

1f.. A,quantity'indicating; device for a liquid container comprising an air pressureY chamber having a perforated bottom, said chamber being'located; in'V and: communicating withj'the liquid at the full' depth to be measured, means Vthrough whi'clrliquid" may be withdrawn from' a pl'ac'e beheath said' chamber?, means' for' restricting the replacement or liquidi from said container to said place' thereby creatingia partial vacuum thereat during the withdrawal of liquid, means for conducting air to: saildfr place as; a'v result of the vacuum thereat, the air" upon?v cessation of the liqnidfiiow being; transferred to. the chamber, aA gauge: located' withoutthe container, and apipe connection .between theV air pressure chamber andithe'gauge: f

-2.1 A quantity indicator comprising a liquid containerhavinglanronen-ing formed'in the bottom y pressure chamber having a concave perforated bottom, a downwardly concave baiie located beneath said bottom, means carried by the ring for securing the air pressure chamber and baiile thereto and Within the container, means for creating a suction beneath said baffle, means for conducting and releasing air beneath said baffie as a result of said suction, said air adapted to rise upward and pass through the perforated bottom, a pressure gauge located without the container, and a hollow connection secured to the air pressure chamber and in communication with the interior thereof and extending to the gauge for conveying the container pressure to the gauge.

3. A quantity indicating device comprising a container having an opening in its bottom, a flanged screw threaded ring secured to the container around said opening, a second screw threaded flanged ring adapted to be screwed to the first mentioned ring, a fluted cup extending upwardly within the container, said cup having its bottom iianged and secured between the screw threaded rings, a deiiecting shield carried by the anged bottom of said cup, said cup and shield having openings formed therein and adapted to permit the passage of liquid from the container to the underside of the shield, an air pressure chamber having a concave perforated bottom secured within the cup above the shield, an air pressure pipe secured to the air pressure chamber and communicating with the interior thereof, said air pressure pipe extending through one of the walls of the container, a gauge located outside the container and secured to said air pressure pipe, an air supply pipe having its one end secured through the wall of the cup and beneath the shield located in said container, its opposite end terminating near the top of the container, and a pipe fitting secured to the bottom of the cup for the purpose of withdrawing liquid from the container.

4. A quantity indicating device for a liquid container wherein the surface of the liquid is open to atmospheric pressure whatever be the level of such surface, comprising a pressure chamber communicating with the liquid at the full depth to be measured, a gauge, a pipe connecting said gauge and pressure chamber, a second pipe having its lower end immersed in the liquid and terminating below said chamber, its upper end being above the normal liquid level, means through which liquid may be withdrawn from a point beneath said chamber, means for restricting the flow of liquid to said point thereby creating a partial vacuum beneath the pressure chamber and uncovering the immersed end of said second pipe whereby air can pass therefrom and be delivered and trapped beneath said pressure chamber and be directed to said chamber.

5. A quantity indicating device for liquids comprising a pressure chamber immersed in and communicating with a liquid at the full depth to be measured, a gauge, a pipe connecting said gauge and pressure chamber, a second pipe having its upper end open to atmosphere and having its lower end immersed in the liquid and below the pressure chamber for conducting free air thereto, means through which liquid may be withdrawn from beneath said pressure chamber, means for restricting the flow of liquid from the container to beneath the pressure chamber thereby creating a partial vacuum and uncovering the immersed end of said pipe and drawing air therefrom, said air adapted to be transferred to the pressure chamber.

6. A quantity indicating device for a liquid container comprising an air chamber in com'- munication with the liquid at the full depth to Vbe measured, a second chamber provided with an aperture for communication with said air chamber below the liquid level therein and being apertured for communication with the liquid in the container and adapted to receive and hold liquid therefrom, means through which liquid may be intermittently withdrawn from the second chamber, means for restricting the flow of liquid from said container toy said second chamber thereby intermittently creating a partial vacuum therein, means for conducting air into said second mentioned chamber as a result of said vacuum, said air then passing into the air chamber, an indicating gauge, and a pipe in communication with said pressure chamber and gauge.

JAMES MACCALLUM, JR. 

